Rotary switch



Nov. 4, 1952 H P, UHN 2,616,994

ROTARY SWITCH Filed May 6, 1948 2 SHEETS- SHEET l M] @/b o o iL-.2.1-kfl@ //0 ATTORNEY Nov. 4, 1952 H, P, LUHN 2,616,994

ROTARY SWITCH Filed May 6, 1948 2 SHEETS-SHEET 2 INVENTOR Patented Nov.4, 1952 RDTARY SWITCH Hansi'. Lulm, Armonk, N. Y.',.assignon to. Inter:Lnational Business, Machines: C..0rporation; New: YorkiN@ Y.,`acorporaton of New.` York.

Application May''; 1948, Serial No. 25,484V

(Cl. milf-11.).

This invention. relatestogeeotrical; units. and.

particulalili.v to a novel; method and; process, of:

construction of: a unit;

The unit. disclosed.' herein". is emplpyedfasgzan;

electrical.'l instrumentality in. an. electric account-y ingrmachine:and is known in `thet art as aacommutator readout unit; or animpulsedistributor,V depending upon-1 its. function. When used asY anemitter, it. is used asasourcemeansv to transmit timed digitrepresenting; impulses= and,- when. used as-av digit readout, itdeterminesthe; digit representing impulses.` to be; transmitted.` Such:functionsv are conveniently exemplified; inthe C; D; Lake'et al. Patent13976,(317, grantedOctober 9; 1934. The: thickness of.` suchunitslwasnot of' importance; in. the machine: of this1 patent,v but. at: thepresentv time; iti is of primet importance in the; construction andidesign.. of present-r commer.- cial electrical; accountingfma-chines,particularly since the time of the patented machine the denominational'.orders of such units have increased to such a number that an accountingmachine would. be; inadvertentlyl large if units previously devisedwere.. employed.. While-,the

present unit is devised as a solution-.to theahove problem,itsincorporationis. notneoessarily confined to this form ofmachineandmay answer the requirements for the design-.ofL a similar unit in anyother formof machine.

It is .the broad object of. theinventon to'devise anlelectricalcommutator unitwhich is practical` in fabrication-.and relatively thin,so thata num-v ber of such unitsmay be assembled in a narrow space, suchas about ten or more to the inch.

Theobject of the inventionis to devise aproc'- ess of fabrication oflanv electrical unit which consists in theiorming of a baseelement ofthin insulating material, drillingv holes at. predetermined` locationsacross the. surface thereof, then. with the aid of' a mask sprayingjoneside ofithe.. element to deposit'. molten metal. thereon form.- inglines. passing through. some: of; the... holes; andY forming metallicareas around others, with the metalentering the holes to .coatthewalls-or. sides thereof, then.. with, the, aid'. of"` another mask.spraying the opposite side ofthe element to deposit molten metal forminglines transverse to the rst lines, said spray also entering the holes.In this manner a commutator element is formed with conductive strips onone side electrically connected through the deposited metal in theholes, with conductive strips on the opposite side of the element. Byinitially drilling holes at selected intersection points, a crossnetwork is built up wherein one set of lines is electrically connectedto another set without employment-.ofi st-:parate;4

Wires or.v connectors; and thefentireassemblyis no; thicker.` than.vthe'. sheetl of'. base;y material. plus thethickness ofithe sprayedlines on the opposite. sides of thea element;

Satisfactoryresults have been obtained by ernploying. a. thin sheet oflaminated phenolic material about 0.020 of an inch in thicknesssandblasted to formr a good adhering surface. Molten zinc: islrstsprayed through a mask to form. lines which have a* goodf affinity with.theI base, and their molten copper is sprayed through the same mask toadhere to thezinc lines.

While the-1 unit formed by the herein describedA process consists .of'a'commutator unit, other elec,- trical. units mayf be: fabricated by thesame processwithout: departingfrom the spirit of theV invention.

OtherA objects of the invention. will.. bei pointed out: in thefollowing description. and claimsY and illustrated' in the4accompanying.v drawings; which;

disclosei by'way of example; the. principlev of. the;

invention andl the best; mode, which. has been.

y contemplated, of applying.' that; principle;

In theadrawings: Fig: 1 isA a view of the base element sl'iapedlandldrilled in" accordance. with a specific crossy con liig 2 showing themanner of `spacing a plurality of`units;

Fig. 5fis a ysection onlines 55-5 of 'Fig'. 2.

The electrical unit consistsprimarily of av thin sheet ofV insulatinglmaterial Ill blanked out from. aY pla-te,v oflaminated phenolic'.material about 0.0201inclr thick, the particular materiali varying withthe requirements with respect to insulating qualities;.rigidity, ease ofmachining,` etc.

Afterthe-sheet I0 hasbeenblanked out to the outline of Fig; l', holesIlI are. drilled alongf the upper' andi lower edgesn and also. holes I2.meansof a template: or guide; smaller-holes'` I3 are drilled in varyingpositions to conform to a predetermined connection pattern. Thereafter,the opposite surfaces of sheet I0 are sandblasted to remove any gloss onthe surface and within the perforations. If, however, the materialemployed has a naturally dull finish, the sanding step is not necessary.As a next step, a mask is placed over` the face of sheet I 0 havingopenings therein forming the pattern of lines and circles as in Fig. 2,and through such openings in the mask a spray of molten zinc is directedagainst the sheet I 0.

The spray enters into and surrounds the holes II and I3, adhering to theinner Walls thereof, and upon removal of the mask the unit will have theappearance of Fig. 2 with the conductive lines 28 thereon. The maskafter cleaning is replaced, and now a spray of molten copper is directedagainst the sheet to superimpose the latter metal upon the zinc.

The steps of successively spraying the zinc and copper through anothermask is then repeated on the opposite side to form the circuit patternof Fig. 3 with lines 2|, 22 and 23 thereon. It will be particularlynoted that the metal spray coats the Walls of the perforations from bothsides so that there is a greater thickness of deposit on the Walls thanupon the plane surfaces and a good conductive path is thereby formedextending through the holes.

Where several units are employed, they may be stacked as indicated inFig. 4, where rods I5 passing through aligned holes I I have nuts I6 toclamp the units together, with washers I'I providing the desiredspacing. A rotary contactor I8 (Figs. 2 and 5) on shaft I9 has one armtraversing the ends of lines 20 and another arm traversing the arcuateline 2| on the opposite side of the sheet II). Thus, with the contactorI8 positioned to contact any line 2B, it electrically connects the holeposition designated C (Fig. 2) through line 22, arc 2I, connector I8 tothe opposite side of the sheet IIJ, line 29, hole I3 and line 23 to oneof the hole positions 9 to 0.

The contactor I8 may correspond to Wiper I ID of Patent 1,976,617wherein it is positioned to represent a Value which can be read out bysending impulses to positions 9, 8, 7, etc. of lines 23 which, when oneof said lines has a hole I3 communicating with the line at whichcontactor I8 is set, Will extend to hole position C which is connectedto a current responsive device.

The unit may also serve as an impulse distributor with contactor I8corresponding to Wiper 219 of the patent (Fig. 13) which rotatescontinuously. It has been found that the lines formed on the sheet inthe manner described constitute a good surface over which a wiper, suchas contactor I8, may be swept repeatedly. In this use of the device,current is supplied to position C and conducted through line 22 to arc2|.and contactor I8. As the contactor rotates, the lines 29 aresuccessively connected to the current source and each in turn Willconduct the current to its related hole I3 and therethrough to aconnected line 23 and hole I I, which latter may be connected tosuitable individual current responsive devices, such as magnets 'I1 or223 of the patent.

While there have been shown and described and pointed out thefundamental novel features of the invention as applied to a singlemodification, it Will be understood that various omissions andsubstitutions and changes in the form and details of the devicesillustrated and in its operation may be made by those skilled in the art4 Without departing from the spirit of the invention. It is theintention, therefore, to be limited only as indicated by the scope ofthe following claims.

What is claimed is:

1. in combination, a plurality of sheets of insulating material, eachhaving a series of digit representating conductive lines spr'ayed'on oneside thereof, means for stacking'said sheets in spaced relationship,conductors, one for each different digit line, to electrically commonthe lines of like digital value on the several sheets, a second seriesof conductive lines on the opposite side of each sheet, variouslyconnected through the sheets with digit representing lines on the firstside of the sheet, and a contactor for each sheet each positionableacross the face of the related sheet to contact With any one of thesecond series of lines whereby current applied to any of the series ofdigit lines will be conducted to all contactors standing ona line of thesecond series that has electrical connection with said digit line.-

sheets With digit representing lines on the first side of the sheet, anda contactor for each sheet each positiona'ole across the face of therelated sheet to contact with any one of the second series of lineswhereby current applied to any of the series of digit lines will beconducted to all contactors standing on a line of the second series thathas electrical connection with said digit line.

` HANS P. LUHN.

- REFERENCES, orrcn The following references 'areof record in the le ofthis patent:

UNITED sTATEs PATENTS Number Name Date 1,954,092 Muller Apr. 10, 1934`2,138,636 Lake i Nov. 29, 1938 2,363,683 Mallina Nov. 28, 1944 2,391,479Rivers Dec. 25, 1945 FOREIGN PATENTS `Number Country Date 686,445 FranceApr. 14, 1930 OTHER REFERENCES Printed Circuit Techniques, by C.Brunetti and PJ. W. Curtis, National Bureau of Standards Circular 468,November 15, 1947.

.New Advances in Printed Circuit, National Bureau of Standards Misc;Publication 192, No-

vember 22, 1948.

Mass-Production Wiring, article in September 1947 issue of fScientificAmerican.

